Russian Foreign Minister Sergei Lavrov sent a tough warning to Iran on Friday, saying its nuclear program could be discussed at the UN Security Council if Tehran fails to respond to Western compromises.

"We reaffirmed that if we see no constructive response from Iran, we will have to discuss the issue at the UN Security Council," Lavrov said following talks in Berlin with his German counterpart Guido Westerwelle.

Iran may face a fourth set of Security Council sanctions over its uranium enrichment activities, which Western powers fear are aimed at building nuclear weapons. Tehran insists its nuclear program is designed for peaceful power generation.

Lavrov said on Friday he will meet with Iranian Foreign Minister Manouchehr Mottaki later in the day in Munich. Lavrov said he will press for "steps to make sure Iran's nuclear program is purely civilian."

Westerwelle said Iran must show willingness for transparency.

Mottaki is to attend the Munich Security Conference, which starts on Friday and involves senior world politicians and officials.

Russia, a veto-wielding Security Council member, has been involved in the long-running nuclear dispute with Iran. Another crucial player, China, has been reluctant to back tougher sanctions.

Chinese Foreign Minister Yang Jiechi said on Thursday discussions on sanctions would "complicate the situation and might stand in the way of finding a diplomatic solution."

The United States and France have spearheaded the six international mediators' drive for new sanctions against Iran, which missed a deadline to accept a deal proposed by the UN nuclear watchdog.

Iranian leader Mahmoud Ahmadinejad, however, indicated on Tuesday a possible change in Tehran's position saying Iran has "no problem" with shipping out its low enriched uranium abroad for further enrichment into 20% fuel for its nuclear research reactor.

BERLIN, February 5 (RIA Novosti)